The pulling of various types of trailers by a vehicle is in common practice. Typically, the vehicle has attached to its rear structure a hollow receiver and the trailer has an insert that is inserted into the receiver and locked in place. Alternatively, the vehicle has attached to its rear structure a ball receiver that is designed to accept a concave ball hitch located on the trailer. In either trailer hitching means, an electrical cable assembly, with or without a cable adapter, is utilized to electrically connect the set of trailer lights to the set of corresponding vehicle lights. The set of lights typically includes a right turn light, a left turn light, a pair of brake lights, a pair of tail lights and a pair of reverse lights.
To verify that an electrical light circuit connection has been made between the vehicle and the trailer, the prior art utilizes a series adapter that incorporates a set of LEDs. If the LEDs illuminate the trailer lights are correctly connected to the corresponding vehicle lights. Conversely, if the LEDs do not illuminate there is a problem with the vehicle-to trailer lighting circuit. The problem with this verification technique is that the driver or passenger must be near the adapter to visually determine if the LEDs are or are not illuminating. Also, to check the brake lights, a first person must depress the vehicle's brake pedal while a second person observes if the LED corresponding to the brake light has or has not illuminated. In contrast, the applicant's light-connection verification technique, in lieu of a visual alert, utilizes an audible sound that can be easily heard from within the cab of the vehicle.
A search of the prior art did not disclose any patents that read directly on the claims of the instant invention, however the following U.S. patents are considered related:
U.S. PAT. NO.INVENTORISSUED5,498,910Hopkins, et al12 Mar. 19965,389,823Hopkins, et al24 Feb. 1995
Both the U.S. Pat. No. 5,498,910 and the U.S. Pat. No. 5,389,823 patents issued to Hopkins, et al, disclose an electrical circuit for adapting the independent brake lights and turn signal lights on a towing vehicle to the combined brake and turn signal lights on an associated trailer. An isolation network and a first CMOS exclusive OR integrated circuit are connected between the right turn signal light connection and brake light connection of the towing vehicle and the combined right turn signal and brake light connection on the trailer. An isolation network and a second CMOS exclusive OR integrated circuit are similarly connected between the left turn signal light connection and brake light connection of the towing vehicle and the combined left turn signal and brake light connection on the trailer. The isolation network prevents feedback from the electrical lighting system of the trailer to the electrical lighting system of the towing vehicle.
In addition to the above patents, industry literature was found that disclosed an adapter that utilizes a set of LEDs to determine if the trailer lights are correctly connected to the vehicle lights. If the LEDs illuminate, the trailer lights are correctly connected. If the LEDs do not illuminate there is a problem with the light circuit. The prior art adapter is manufactured by the Hopkins Manufacturing Corporation, U.S.A.